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This pillbox is of the Type FW23, one of several designs produced by the Army to defend against the expected German invasion after France fell in 1940. It comprises two sections one roofed, the other open for a light anti-aircraft gun. The roofed section has three embrasures or gun loops. Access was by a iron ladder cast into the rear wall. This has since rusted away.

Originally of course the pillbox would have been on top of the dunes. This illustrates the extent of erosion of the coast over the intervening sixty years.